Method of making cement-coated wire



UNITED STATES PATENT OFFICE- .r'nmcnann GREEN, or cnrcaeo, rumors,assrenon TO cfiroaoo s'rnnr. AND wmr.

COMPANY, OF CHICAGO, ILLINOIS, AOOBPORATION OF ILLIHOIS METHOD OF MAKINGCEMENT-COATED WIRE Io Drawing. Application filed November 23, 1927.Serial No. 285,402,.

The object of my invention is to apply a quite liquid, every contactbetween adjacent film or layer of cementing material to a mestrands ofwire and also every contact with tallic wire or strip in such a mannerthat the supporting mandrel disturbs or roughens the coating is smooth,flexible, hard and suitablefor use in an automatic forming machine 1without serious interference with the operation of such machine, saidcoating increasing the holding power of fastening devices made from thewire when driven into wood or like materials. I

My invention relates to the application of such a coating to continuouslengths or coils of wire, in distinction to wire after it has beenformedinto various articles, such as staples, nails, and the like. Ihave found that there are only a few methods by which this can be donesatisfactorily. One method, for example, is to draw the wire through asolution or dip. Another is to spray the coating -material onto thewire, either as a single strand or in the coil. Still another is to dipthe coil in the solution. While these represent the fundamentalmethods,- the details may differ. For instance, the material may beapplied hot or cold; it may be a solution at ordinary temperatures; orit may be a material which must be fused in order to make it liquid,etc. I

I prefer to dip the wire in coils because less equipment is required,the equipment necessary is quite inexpensive, and the process isaltogether simpler andchcaper to per.-

form as .a manufacturing operation. However, when the wire is dipped'asa coil in any cementing material, the material, being gummy, willnaturally cause the various strands to adhere together and prevent asmooth coating being formed. I have discovered that I can overcome thisby spreading the coil of wire out on a mandrel which is of substantiallyless diameter than the inside diameter of the coil of wire, and rotatingthe mandrel during the drying of the coating material, whereby ashifting contact between the supporting mandrel and the wire isobtained. Immediately after dipping the coil, the coating material is,quite liquid, and as this coating material dries, or

solidifies, it changes gradually from a liquidto a solid. While thecoating material is the coating. I have found, however, that the momentthe point of contact, either between adjacent strands or with thesupporting man- 'drel, is shifted, the coating material tends to spreadout again over the surface of the wire and heals the roughened spot. Bythe time the same point on the wife makes another contact, the coatingmaterial is more nearly solid and the contact does not roughen it quiteso much. On the other hand, it has a slower tendency to heal but I havediscovered that these two tendencies may be made to balance .out in sucha way that the tendency to heal the roughened spots is greater than thetendency to produce such spots.

The result is that when the coating material is dried or solidified, thewire is smoothly and evenly coated. I have found that the tendencytoward a smooth coating, when the wire is dipped as a coil and thecoating material dried or solidified on a shifting. contact, such as therotating mandrel described, is such that it is not necessary to shiftthis contact continuously, although, of course, continuous shifting orrotating of the mandrel is desirable. I

While there are a number of liquids suitablefo-r dipping the coils ofwire, I prefer to use the following: b

- a s y weight China wood oil 3O Glycerine ester, rosin 20 Petroleumnaphtha 50 The above mixtureshould be diluted with additional naphtha togive the proper thickness of coating on the finished wire, whichthickness varies with the shape, size and exact use to which the wire isput. I may also add small quantities, about 1%, of dryers such aslitharge, manganese dioxide, etc., as may be desirable to-assis't thecoating in taking its set or losing its tackiness quickly while drymg.drying and usually produces a harder, smoother coating. j

Also I prefer to add a pigment, such as Heat and/or moving air alsoassists in" tification in the Wire mill in which the wire is made or inthe users hands.

Still another mixture is as follows:

Parts by weight Rosin; 15.0 -Hydrated lime 0.9 Litharge 0.3 Manganesedioxide 0.2 China wood oil 33.6 Naphtha 50.0 The rosin, salts and oilare cooked to a heavy body and thinned with the naphtha,

after which additional naphtha and pigment is added as required. In bothof the above formulae, turpentine or coal tar naphtha may be used as asolvent or dilutent. It will be seen that in both of the mixtures thecombined properties of a rosin like substance and a lon oil or varnishare provided.

I c aim:

1. The method of coating a wire, which consists in applying to the wirein coil form the coating material in a liquid form, and drying the "wirewhile suspended on a rotating support upon which it is constantlychanging its position thereon.

2. The method of cement coating 3. wire, which consists. in applying toa coil of the wire the cementing material in liquid form, extending thecoil, placing the extended coil loosely upon a support and rotating thesupport.

3. The. method of cement coating a wire, which consists in applying to acoil of the wire the cementing material in liquid form, suspending thecoil loosely upon a rotating support positioned within the coil, anddrying the coil.

4. The method of cement coatin a wire, which consists of applying to a0011 of the wire the cementing material'in liquid form, extending thecoil, suspending it loosely upon a support positioned withinthe coil,rotating the support and drying the coil.

5. The method of cement coating a wire, which consists in dipping thewire in a coil in a liquid cementing material, extending it, placing itupon a support, dryin the coil and shifting the support relative y tothe coil during the drying operation.

6. The method of coating a wire, which consists in applying the coatingmaterial as a liquid to the wire, placing the wire upon a support,solidifying the material on the surface of the wire, and continuouslyshifting the support with respect to the wire during the solidificationoperation.

7. The method of coating a wire, which consists in applying to thesurface thereof materialshaving the gumminess of rosin, and theflexibility of a long oil or varnish, placing the wire upon a support,and constantly changing the position of the wire upon the support duringthe time such materials are solidifying on the surface, whereby toobtain a smooth and uniformly distributed coating.

scribed my name.

J BIRCHARD GREEN.

